On first generation small-block Chevy engines, lifters were either hydraulic flat-tappet or solid flat-tappet, with hydraulic roller and solid roller designs available in the aftermarket. Read: SBC Timing Chain, Gears, and Cover Hydraulic Lifters Since automotive emission standards were going to get even stricter in the 1980's, GM engineers began working on electronic fuel injection systems to replace the over-burdened carburetor. The first small-block Chevy to have fuel-injection was 1957, an additional cost option which gradually faded away in 1965.īy the mid 1970's, SBC engines were being equipped with emissions and engine function controls, neither of which carburetors were ever designed to handle. This is only required if you plan on making serious horsepower (500+) at very high revs (over 6,000 rpm).īefore doing this, consider selling your vintage block to a restorer and building yourself a 350ci motor. Neither 283 nor 327 Chevy blocks ever left the factory with four-bolt main caps, but they can be added. If you're looking to build a healthy street motor, there's nothing wrong with a 2-bolt main block.īut if your small-block Chevy build includes a high revving motor (over 6,000 rpm) and 500+ horsepower, and 4-bolt block is a good idea. The horsepower level was near 600 before any main cap movement was detected. There was a tech article several years back where an engine builder tested a 2-bolt block to see how much power it would take before main cap flex. The center-three main caps in the 4-bolt block had two additional bolts which were supported by the addition of heavier crankcase main-web bulkheads. Many builders will start with the specs of an LT1 small-block and then customize it to their liking.Ĭhevy 350 small-blocks were made with either 2-bolt or 4-bolt main bearing caps.

The LT-1 featured a solid lifter cam, 11:1 compression, a 780cfm Holley four-barrel carburetor, and aluminum intake manifold. Power output was 370-horsepower in the Corvette, and 360-horsepower in the Camaro Z/28. The 350 LT-1 motor was the highest horsepower version of the Gen-One small-block Chevys. Read: Spray Paint Engine LT-1 Small-Block

Chevy 350 history